1. FIELD OF INVENTION
The present invention relates to a process for the preparation of liquid resinous compositions, and it is a primary object of the present invention to provide an aqueous resinous composition which can be used for various purposes, for example, as a film-forming composition for adhesives, coatings, printing inks, a binder and the like.
2. DESCRIPTION OF PRIOR ARTS
On the background of recently increasing social concerns on problems of evironmental pollutions and saving of petroleum resources, as is well known in the art, various efforts and attempts have been made to provide solvent-free compositions that can be used instead of film-forming compositions containing large quantities of organic solvents, which have heretofore been used in fields of adhesives, paints printing inks, paper- and fiber-finishing agents and the like. Among some expected solvent-free technological systems, water-based compositions may provide the most immediately feasible means and be applied with minimum modification of present equipment. Synthetic resin emulsions obtained by emulsion polymerization or aqueous resin solutions formed by dissolving water- or alkali-soluble resins in water or aqueous alkaline solution have heretofore been used as aqueous film-forming components and binders. Resin films or coating formed from such aqueous compositions, however, are generally defective in that the water resistance is poor and the drying property is inferior. Further, even if it is intended to crosslink and cure the film obtained from such aqueous compositions, the water-soluble curing agents having a good curing property at low temperatures is much limited and it is difficult to obtain cured films having a good water resistance. Accordingly, at the present, replacement of organic solvent based compositions by aqueous compositions involves various difficulties and cannot be accomplished with ease.